hihocoder 后缀自动机二·重复旋律5

求不同子串个数

裸的后缀自动机

 #include<cstring>
 #include<cmath>
 #include<iostream>
 #include<algorithm>
 #include<cstdio>

 #define ll long long
 #define N 2000007
 using namespace std;
 inline int read()
 {
     int x=,f=;char ch=getchar();
     while(!isdigit(ch)){if(ch=='-')f=-;ch=getchar();}
     while(isdigit(ch)){x=(x<<)+(x<<)+ch-'';ch=getchar();}
     return x*f;
 }

 int n;
 ll ans;
 struct sam
 {
     int last,cnt;
     int c[N][],fa[N],mx[N];
     sam(){last=cnt=;}
     void extend(int x)
     {
         int p=last,np=last=++cnt;mx[np]=mx[p]+;
         while(p&&!c[p][x])
         {
             c[p][x]=np;
             p=fa[p];
         }
         if(!p)fa[np]=;
         else
         {
             int q=c[p][x];
             if(mx[q]==mx[p]+)fa[np]=q;
             else
             {
                 int nq=++cnt;mx[nq]=mx[p]+;
                 memcpy(c[nq],c[q],sizeof(c[q]));
                 fa[nq]=fa[q];
                 fa[q]=fa[np]=nq;
                 while(c[p][x]==q)c[p][x]=nq,p=fa[p];
             }
         }
     }
 }sam;
 char s[N];

 int main()
 {
     scanf("%s",s+);n=strlen(s+);
     for (int i=;i<=n;i++)
         sam.extend(s[i]-'a');
     for (int i=;i<=sam.cnt;i++)
         ans+=sam.mx[i]-sam.mx[sam.fa[i]];
     printf("%lld",ans);
 }